--- /dev/null
+diff -up openssl-1.0.0c/apps/genrsa.c.x931 openssl-1.0.0c/apps/genrsa.c
+--- openssl-1.0.0c/apps/genrsa.c.x931 2010-03-01 15:22:02.000000000 +0100
++++ openssl-1.0.0c/apps/genrsa.c 2011-02-01 18:32:05.000000000 +0100
+@@ -95,6 +95,7 @@ int MAIN(int argc, char **argv)
+ int ret=1;
+ int i,num=DEFBITS;
+ long l;
++ int use_x931 = 0;
+ const EVP_CIPHER *enc=NULL;
+ unsigned long f4=RSA_F4;
+ char *outfile=NULL;
+@@ -138,6 +139,8 @@ int MAIN(int argc, char **argv)
+ f4=3;
+ else if (strcmp(*argv,"-F4") == 0 || strcmp(*argv,"-f4") == 0)
+ f4=RSA_F4;
++ else if (strcmp(*argv,"-x931") == 0)
++ use_x931 = 1;
+ #ifndef OPENSSL_NO_ENGINE
+ else if (strcmp(*argv,"-engine") == 0)
+ {
+@@ -273,7 +276,14 @@ bad:
+ if (!rsa)
+ goto err;
+
+- if(!BN_set_word(bn, f4) || !RSA_generate_key_ex(rsa, num, bn, &cb))
++ if (use_x931)
++ {
++ if (!BN_set_word(bn, f4))
++ goto err;
++ if (!RSA_X931_generate_key_ex(rsa, num, bn, &cb))
++ goto err;
++ }
++ else if(!BN_set_word(bn, f4) || !RSA_generate_key_ex(rsa, num, bn, &cb))
+ goto err;
+
+ app_RAND_write_file(NULL, bio_err);